The present invention relates to a method of manufacturing a printed wiring board, more particularly, to a printed wiring board in which a printed circuit is formed on a substrate, an insulating layer is coated on at least a part of the printed circuit, a shield layer is coated on at least a part of the insulating layer.
Such a printed wiring or circuit board is well known from, for example, the Japanese Utility Model Application Publication No. 29,276/80. In this case, the shield layer is usually obtained by coating copper paste over desired portions of the insulating layer.
The coating of the above shield layer is performed by coating the copper paste substantially over the whole surface of the insulating layer with a screen process printing, so that the new provision of a mask for printing may be omitted. However, this method must increase the desired amount of the copper paste so that heat dissipation of the printed circuit board becomes decreased and the shield layer is susceptible to cause cracks in the drying process.